मराठी

Find the sum of the following series to infinity: 10 − 9 + 8.1 − 7.29 + ... ∞

Advertisements
Advertisements

प्रश्न

Find the sum of the following series to infinity:

10 − 9 + 8.1 − 7.29 + ... ∞

बेरीज
Advertisements

उत्तर

This infinite G.P has first term a = 10 and common ratio r = `-9/10 = -0.9`

Thus the sum of the infinite G.P will be:

10 - 9 + 8.9 - 7.29 +  ... ∞ = `"a"/(1-"r")` [Since |r| < 1]

= `10/(1-(-0.9))`

= `10/1.9`

= `100/19`

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
पाठ 20: Geometric Progression - Exercise 20.4 [पृष्ठ ३९]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 11
पाठ 20 Geometric Progression
Exercise 20.4 | Q 1.4 | पृष्ठ ३९

व्हिडिओ ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्‍न

Find the 20th and nthterms of the G.P. `5/2, 5/4 , 5/8,...`


The 5th, 8th and 11th terms of a G.P. are p, q and s, respectively. Show that q2 = ps.


Find the sum to 20 terms in the geometric progression 0.15, 0.015, 0.0015,…


Find the sum to indicated number of terms in the geometric progressions 1, – a, a2, – a3, ... n terms (if a ≠ – 1).


Find the sum to indicated number of terms in the geometric progressions x3, x5, x7, ... n terms (if x ≠ ± 1).


Evaluate `sum_(k=1)^11 (2+3^k )`


Find the sum to n terms of the sequence, 8, 88, 888, 8888… .


If a, b, c and d are in G.P. show that (a2 + b2 + c2) (b2 + c2 + d2) = (ab + bc + cd)2 .


Find : 

nth term of the G.P.

\[\sqrt{3}, \frac{1}{\sqrt{3}}, \frac{1}{3\sqrt{3}}, . . .\]


The sum of first three terms of a G.P. is \[\frac{39}{10}\] and their product is 1. Find the common ratio and the terms.

 

The product of three numbers in G.P. is 216. If 2, 8, 6 be added to them, the results are in A.P. Find the numbers.


Find the sum of the following geometric progression:

1, 3, 9, 27, ... to 8 terms;


Find the sum of the following geometric series:

x3, x5, x7, ... to n terms


Evaluate the following:

\[\sum^n_{k = 1} ( 2^k + 3^{k - 1} )\]


Find the sum of the following series:

0.6 + 0.66 + 0.666 + .... to n terms


The sum of three numbers in G.P. is 56. If we subtract 1, 7, 21 from these numbers in that order, we obtain an A.P. Find the numbers.


If a, b, c are in G.P., prove that:

\[a^2 b^2 c^2 \left( \frac{1}{a^3} + \frac{1}{b^3} + \frac{1}{c^3} \right) = a^3 + b^3 + c^3\]


If a, b, c, d are in G.P., prove that:

\[\frac{ab - cd}{b^2 - c^2} = \frac{a + c}{b}\]


If a, b, c, d are in G.P., prove that:

(a2 + b2 + c2), (ab + bc + cd), (b2 + c2 + d2) are in G.P.


If pth, qth, rth and sth terms of an A.P. be in G.P., then prove that p − q, q − r, r − s are in G.P.


Find the geometric means of the following pairs of number:

2 and 8


If (p + q)th and (p − q)th terms of a G.P. are m and n respectively, then write is pth term.


If pth, qth and rth terms of a G.P. re x, y, z respectively, then write the value of xq − r yr − pzp − q.

 

 

 


The value of 91/3 . 91/9 . 91/27 ... upto inf, is 


The sum of an infinite G.P. is 4 and the sum of the cubes of its terms is 92. The common ratio of the original G.P. is 


Check whether the following sequence is G.P. If so, write tn.

7, 14, 21, 28, …


For the G.P. if r = `1/3`, a = 9 find t7


For the G.P. if r = − 3 and t6 = 1701, find a.


Find three numbers in G.P. such that their sum is 21 and sum of their squares is 189.


For the following G.P.s, find Sn

3, 6, 12, 24, ...


For a G.P. sum of first 3 terms is 125 and sum of next 3 terms is 27, find the value of r


Determine whether the sum to infinity of the following G.P.s exist, if exists find them:

9, 8.1, 7.29, ...


Find `sum_("r" = 0)^oo (-8)(-1/2)^"r"` 


Select the correct answer from the given alternative.

If for a G.P. `"t"_6/"t"_3 = 1458/54` then r = ?


Answer the following:

In a G.P., the fourth term is 48 and the eighth term is 768. Find the tenth term


Answer the following:

If for a G.P. t3 = `1/3`, t6 = `1/81` find r


For a, b, c to be in G.P. the value of `(a - b)/(b - c)` is equal to ______.


The sum or difference of two G.P.s, is again a G.P.


The sum of infinite number of terms of a decreasing G.P. is 4 and the sum of the terms to m squares of its terms to infinity is `16/3`, then the G.P. is ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×